Unit 43: Nervous System

Test on April 3

What does nervous system do?

controls and coordinates all body functions

Neourons-

cells of nervous system

how many pairs of spinal nerves?

31

how many pairs of cranial nerves

12

*what are nerves*

nerves are bundles of dendrites and axons

central nervous system (CNS):

-made up of the brain and spinal cord

-surrounded by bone

-protected by membranes called meninges

• surrounded by cerebrospinal fluid

Nerves are apart of

peripheral nervous system

Myelin Sheath-

(fat covering over the nerves), its over the dendrites and acts as insolation protecting the nerves.

cerebrum

largest part of the brain. It has folds in it called Convolutions.

cerebellum

found beneath occipital lobe of cerebrum

Brain Stem

connects brain to spinal cord. Controls heart, blood vessels, and lungs.

-- instant death if severed.

Spinal Cord

nerves entering and leaving spinal cord carry impulse to and from control center, (in the brain).

meninges-

membranes surround brain and spinal cord, to protect.

cerebrospinal fluid

flows around brain and spinal cord and cushions it against shock & possible injury.

Peripheral Nervous System (PNS)

nerve structure outside brain and spinal cord.

reflex-

involuntary response to a stimulus

(taking a hand off a hot stove)

eye

hollow ball filled w 2 liquids

the sclera

tough white outer coat that is protective.

cornea

the transparent layer forming the front of the eye. light rays pass through cornea into the eye.

retina

intermost layer, made up of neurons (nerve cells), that are sensitive to light.

iris

colored portion of the eye, a muscle found behind cornea.

pupil

opening that light goes in. opening in iris.

Conjunctiva

mucus membrane that lines eyelids & covers eye.

lacrimal glands

makes tears.

Pinna

outside of ear, also Called auricle.

tympanic membrane (eardrum)

divides outer and middle ear.

ossicles

tiny bones in back of eardrum.

Eustachian tube

leads from throat to middle ear, to equalize pressure on either side of eardrum.

Cochlea

looks somewhat like a coiled snail shell. In your inner ear

Aging Changes affecting eyes + ears:

-cataracs or glaucoma,(pressure in eye) develop.

-hearing declines

-sight declines

-tear prod. decreases causing discomfort.

-pupil reacts more slowly in reaction to dark/bright lights.

-Increased intacranial,(in brain/head) pressure

-intracranial bleeding due to ruptured blood vessels, this is called a CVA (cerebrovascular accident

signs and symptoms of intracranial pressure

-headache

vommiting

change in metal status

loss of consciousness

Transient Aschemic Attacks(TIA)

def: a temporary period of diminished blood flow to the brain.

-comes rapidly and can last 2-15mins or 24 hours.

-people who have had a TIA are at risk for a stroke

-stroke is the leading cause of disability in US

-2 causes of stroke are

aneurysm or blood clot

complete or partial loss of blood flow to brain tissue is frequently a complication of-

Atherosclerosis or brain hemmorige

signs + symptoms of a stroke

-headache

vommiting

paralysis

sight problems

convulsions

weakness on one side

diff. w speech

hemiplegia

hemiparesis

-hemyplegia

(paralyzed one side)

-hemiparesis

weakness one side

paraplegia-

paralysis lower part of the body

quadriplegia

paralysis of all four limbs

preventing complications caused by immobility

- ROM

-use pillows for turning pt

-prevent pneumonia

-move pt and use ted stockings

3 therapies

PT, OT, and speech therapy

care to prevent contractures

-turn pt every 2 hours

-positioning

-using pillows and ROM

parkinsons disease

caused by not having enough dopamine in brain stem and cerebellum

signs + symptoms of Parkin sons

-tremmers

pill rolling

muscular rigidity

shuffle while walking

diff. starting/stopping ambulation

slurred speech

Multiple Sclerosis (MS)

-cause is unknown, is autoimmune.

occurs in young people

will have feelings of numbness and tingling

vertigo

How to diagnose MS

MRI

signs and symptoms MS

-1/2 people have problem w vision

pain in legs ,especially w cold weather

spasticity of muscles

- in severe MS, speech is affected bc of muscle weakness

Lou Gehrigs disease

a disease of motor nerves that control voluntary movement.

cause is unknown, no cure

most common age of onset is 55 years old

signs and symptoms of Lou Gehrigs

-stumbling, tripping, falling

loss of strength and muscle control in arms and legs

diff speaking

high choking risk bc difficulty swallowing

Not a painful disease.

Seizure Disorder (Epilepsy)

-seizure disorder is also called convulsions or epilepsy.

-some people experience aura before seizure, see/hear/smell something indicating the seizure.

grand mal seizure

tonic chlonic seizure. Loss of consciousness occurs. muscles will stiffen and jerk.

After grand Mal: person will be tired.

never hold a person down, and get head on ur knees if you can.

diagnosis w EEG

treat w/ oral medicine. some medicine have side affects causing your teeth to be grey or gums grow over teeth.

petite mal seizures

momentary loss of muscle tone. Seizure begins w/ out warning. Period of unconsciousness. seizure lasts 2-10 seconds. pt blinks, breathes rapidly, stares blankly.

partial seizure

involves 1 side of the body. most of the time, there is no consciousness.

nurse care during seizures

- stay w person

assist pt to lie down

protect the head

do not restrict pt

turn on side to maintain airway

be calm when they’re out of the seizure

Spinal Cord Injuries

paralyzed from the injury down.

resp. of CNA when pt has paralysis

encourage the pt to make choices about things that affect them.

listen to pt

careful skin care (turning, using pillows, change quickly)

Meningitis

it is the inflammation of the meninges, usually caused by bacteria or viruses.s

signs and symptoms of meningitis

seizures

chills

nausea

stiffness of neck

elevated temp

Cataracts

leading cause of vision loss in adults 55+

causes normal clear lens to become cloudy

Treatment: surgery, putting in replacement lenses.

Glaucoma

condition of increased pressure within the eye

• given eye drops sometime surgery.

retinal or macular degeneration

break down of retina, occurs over time.

central vision is lost.

Artificial EYE

some pts remove it at night. when its taken out, put it in a marked cup w/ sterile saline solution or contact solution.

Caring for eye and socket (artificial eye)

this is not a sterile procedure. you will need labeled cup, cotton balls, and gloves.

wipe outer eye while in socket with moistened cotton ball.

remove eye by gently holding down eyelid w thumb, open upper lid w/ index finger.

grasp eye as it comes out of socket and place it on gauze in cup w/ solution.

Putting eye back in

• take gauze and clean inside socket w/ water

• insert eye into socket using gloves.

• notice notched edge

• gently open upper eyelid and slips into Lower lid.

otitis media

infection of middle ear.

take care w/ antibiotics

otitis externa *****

external canal leads to eardrum.

infection of outer ear

known as swimmer ears and treated with antibiotics.

***When caring for deaf pts or hearing impaired pts, keep pitch of your voice low, do not speak loudly or yell. always face them**

Hearing Aids

• hearing aids rechargeable

• make sure aids are out at night and in a safe place.

• keep dry

• turn them off when taken out

• there is a way to tell which side goes on what ear.

ex: blue, left. red, right